[Laravel] Laravel's basic database operation part, laravel database_PHP tutorial

[Laravel] The basic database operation part of Laravel, laravel database

[laravel] The database configuration of laravel

Find the .env file under the program directory structure

Configure basic database connection information

DB_HOST=127.0.0.1

DB_PORT=3306

DB_DATABASE=blog

DB_USERNAME=root

DB_PASSWORD=root

After modifying the .env file, you need to restart the service

[laravel] Getting started with the database of laravel

Import the DB database operation class into the controller, use DB

Use the static method select of the DB class to query the database, DB::select(), parameters: sql statement, parameter value array

For example: $user=DB::select("select * from article where id=?",array("1"));

Get an array, each result in the array is a StdClass object

<?<span>php
namespace App\Http\Controllers\Index;
</span><span>use</span><span> App\Http\Controllers\Controller;
</span><span>use</span><span> DB;
</span><span>class</span> IndexController <span>extends</span><span> Controller{
    </span><span>public</span> <span>function</span><span> index(){
        </span><span>$data</span>=<span>array</span><span>();
        </span><span>$data</span>['title']="Index控制器"<span>;

        </span><span>//</span><span> 第一种</span>
        <span>$user</span>=DB::select("select * from article where id=?",<span>array</span>("1"<span>));
        </span><span>foreach</span> (<span>$user</span> <span>as</span> <span>$v</span><span>) {
            </span><span>echo</span> <span>$v</span>-><span>title;
        }
        </span><span>//</span><span> 第二种</span>
        <span>$users</span>=DB::table("article")-><span>get();
        </span><span>foreach</span> (<span>$user</span> <span>as</span> <span>$v</span><span>) {
            </span><span>echo</span> <span>$v</span>-><span>title;
        }
        </span><span>return</span> view("index.index",<span>$data</span><span>);
    }
}</span>

Use Query Builder

Use DB::table() to get the query constructor object, parameters: table name

Call the get() method of the Builder object to get the array data

For example: $users=DB::table("article")->get();

The query constructor is called in a chain. There are other methods, you can check the documentation

[laravel] Database migration

Use Artisan command to create migration, make:migration name –create table name

For example: php artisan make:migration create_users_table --create=users

This command will create a migration file under the database/migrations directory

Open the generated migration file and create fields in the up method. The database structure constructor Schema will be used here

Run the migration command, use the command php artisan migrate, the table will be automatically created in the database

[laravel] EloquentModel

Use the Eloquent model to create a mapping model ORM for the table, and use the Artisan command make:model model name

For example: php artisan make:model User

Generate a User.php model file in the app directory